JUPITER, Fla. (AP) - Lance Berkman needed to see his name on a St. Louis Cardinals jersey for the switch to sink in: After 13 spring trainings with the Astros, he had joined Houston's NL Central rival.

"Oh my goodness, there it is," he said when seeing his No. 12 jersey hanging from his locker last week. "We're ready to go now."

The 35-year-old agreed in December to an $8 million, one-year contract. He had spent his entire big-league career with the Astros before he was traded to the New York Yankees last July.

Berkman said he felt like "a fish out of water" in New York. Now he joins a former foe.

"As heated as the rivalry got between Houston and St. Louis, it never got to the point of nastiness," Berkman said. "There was a healthy respect certainly from us towards them. I think it was a mutual respect."

A first baseman in recent years, Berkman is being asked to play the outfield for the first time since 2007. St. Louis needs to replace Ryan Ludwick, who was sent to the Padres last July.

St. Louis never did settle on a right fielder or a No. 5 hitter behind Albert Pujols and Matt Holliday.

"It's got the potential to be a great middle of the order," Berkman said. "I think the question mark is me. I think you know what you're going to get out of Albert. Matt is very consistent and is a great hitter. Just a matter of how am I going to hit this year."

Berkman is looking to rebound from the worst season of his career. He hit .248 with 14 home runs and 58 RBI while recovering from knee surgery in March. He put himself though a rigorous offseason training program, working on his speed, agility, explosiveness and strength four days a week.

Berkman insists playing right field will not be an issue, despite just 74 starts there the last six seasons. He said he's played enough outfield during his career to understand the position. He believes the biggest challenge will be the swirling wind during spring training.

"Spring training is a circus when it comes to playing the outfield," he said. "I'll guarantee you there'll be at least a ball or two misplayed just because of the conditions. Overall, if they hit it in the air you go catch it. If they hit it on the ground you pick it up and throw it to the guy. I don't think it's going to take me very long to feel good out there."

La Russa is more concerned Berkman isn't pushed - because of his age and knee.

"Everybody knows he's a productive player," La Russa said. "I know he is going to make the routine play. Whatever else he does beyond that is a plus. My only concern is just making sure we keep him healthy enough."